Generator Set Is The Key Equipment Of Hydropower Station

Energy is the material basis of social development and the support and power of national economic growth.  Energy is not only closely related to human development, but also plays an irreplaceable role in social and economic development.  In today's Energy consumption structure in China, fossil energy is still dominant, and the contradiction between the limited energy and the increasing demand is increasingly fierce, which has become a bottleneck restricting the social and economic development.  In this situation, as a kind of renewable energy, hydropower entered the historical stage and occupied an important position.  Global energy consumption is expected to increase 1.5 times from 1174.3 billion tons in 2010 to 175.17 billion tons in 2035.  Fossil fuel consumption now accounts for about 90 percent.  Changes in natural resources and clean energy must be further explored because of non-renewable fossil fuels and their environmental and health impacts.  Hydropower accounts for 15% of the world's electricity supply and is a major source of renewable and sustainable energy.  

The turbine is the heart of any hydropower station, converting the potential energy of water into mechanical energy.  The hydro-generator set is the key equipment of the hydropower station, and its safe operation is the fundamental guarantee to ensure the safe, high-quality and economic power generation and power supply of the hydropower station. It is directly related to the safe and stable operation of the power grid, and determines the economic and social benefits of the hydropower station.  The results show that the hydraulic stability caused by turbulent pulsation of turbine is an important factor to determine the operation stability of turbine.  In fact, in the operation process of hydropower units, vibration is often caused by mechanical and electrical reasons in addition to the vibration caused by hydraulic instability.  According to statistics, about 80% of failures or accidents of hydropower units are reflected in vibration signals.  Therefore, it is of great significance to study the fault diagnosis method of hydropower unit and make intelligent diagnosis of vibration fault of hydropower unit for improving the fault diagnosis level of hydropower unit in China and narrowing the gap with similar technology abroad.  

With the increasing of capacity and structure scale of hydro-generator unit, the stability of unit operation has become an urgent scientific and engineering problem to be studied.  In-depth analysis of vibration mechanism of hydro-generator unit can better ensure its reliability of operation and effectively avoid or reduce the possible harm caused by vibration failure to the unit.  It is of great practical significance to understand the vibration of hydraulic turbine.  

The main causes of mechanical vibration are:  

Improper alignment of the large shaft at the flange, loosening of the connection or loosening of the fixing parts lead to vibration of the large shaft broken line;  

Vibration of the rotating part of the unit due to mass imbalance, bending or falling off of parts;  

Vibration caused by friction between the rotating part and the fixed part of the unit, large gap between the guide bearing bush, uneven thrust bearing bush, loose thrust head and so on.  

The vibration caused by mechanical defects or faults has common characteristics. The vibration frequency is frequency conversion or multiple frequency conversion, and the unbalanced force is radial or horizontal.  

Electromagnetic vibration can be divided into two kinds: rotational frequency vibration and polar frequency vibration.  The electromagnetic causes of frequency conversion vibration are mainly short circuit of rotor winding, uneven air gap of fixed rotor, asymmetric operation and wrong order of magnetic poles, resulting in magnetic circuit asymmetry, magnetic tension imbalance and vibration.  Stator core loosening causes 100Hz extreme frequency vibration.  

Guangxi Dingbo Power Equipment Manufacturing Co., Ltd. established in 2006, is an manufacturer of diesel generator in China, which integrates design, supply, commissioning and maintenance of diesel generator set. Product covers Cummins, Perkins, Volvo, Yuchai, Shangchai, Deutz, Ricardo, MTU, Weichai etc. with power range 20kw-3000kw, and become their OEM factory and technology center.